With the improvement of surgical concept and techniques, minimally invasive surgery has entered a new era.Transanal Endoscopic Microsurgery is a minimally invasive surgical procedure for rectal tumor, with little trauma, simple procedure, clear operative field, few complications and many other advantages.It is gradually being accepted nowdays, but the preoperative staging and indications for surgery requirements are much strict, so it should be undertaken with caution in clinical work.Now the indications, preoperative evaluation, surgical complications and efficacy evaluations will be briefly described.